tools: modernize and optimize doc/addon-verify.js

Modernize:
* Replace `var` with `const` / `let`.
* Replace common functions with arrow functions.
* Use destructuring.
* Use `String.prototype.padStart()`, `String.prototype.endsWith()`.

Optimize:
* Reduce function calls.
* Reduce intermediate variables.
* Cache retrieved object properties.
* Move RegExp declaration out of a cycle.
* Simplify RegExps.
* Replace RegExp with string when string suffices.
* Remove conditions that cannot be false.
* Replace for..in with `Object.keys().forEach()`.

Also, eliminate needlessly complicated function chains:
* `ondone` callback only checks errors;
* if there is an error, it is called once and throws, then script exits;
* if there are no errors, it is noop;
* so there is no need to wrap it into `once()` function
* and there is no need to call it without errors;
* we can eliminate it and replace with `throw` where an error occurs;
* we can also replace `onprogress` callback with `console.log` in place;
* at last, we can eliminate `waiting` counter and `once()` utility.

The new script produces results identical to the old ones.

PR-URL: https://github.com/nodejs/node/pull/20188


Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>